Childhood Myelogenous Leukaemia
Contents:
Leukaemia is a cancer of the blood-forming cells, most commonly white blood cells. Leukaemia starts in the bone marrow, from there it can spread to the blood, lymph nodes, spleen, liver, central nervous system, and other organs. Both children and adults can develop leukaemia, however leukaemia is the most common child hood cancer.
Types of Leukaemia
Leukaemia can be either acute (rapidly growing) or chronic (slower growing). Almost all leukaemia in children is acute. Acute leukaemia is divided into 2 types:
1. acute lymphocytic leukaemia (referred to as ALL)
For information on Childhood Acute lymphocytic leukaemia (ALL) please see relevant fact sheet.
2. acute myelogenous leukaemia (referred to as AML)
Acute myelogenous leukaemia is less common than ALL. It is a cancer of the bone marrow cells that form granulocytes, monocytes, red blood cells, or platelets.
AML is divided in to different groups based on the type of blood cell that are affected, how developed the cancer cells are at the time of diagnosis, and how different they are from normal cells. The treatment for most subtypes of AML is similar apart from acute promyelocytic leukaemia (APL) that is treated differently.
For the most part, lifestyle risk factors such as diet and exercise are not linked to childhood cancers.
Race
Hispanics are more likely to develop AML.
Genetics/family history
Having a brother or sister with AML especially a twin increases the risk of developing the disease.
Genetic disorders
Certain genetic diseases that cause children to be born with an abnormal immune system increase their risk of developing AML. Conditions such as Li-Fraumeni syndrome, Down's syndrome, Klinefelter's syndrome and others carry an increased risk of AML.
Myelodysplastic syndromes
Myelodysplastic syndromes may progress to AML. In myelodysplastic syndromes, the bone marrow makes too few red blood cells, white blood cells, and platelets. These blood cells may not mature and enter the blood.
Chemotherapy
Past treatment with chemotherapy or other drugs that weaken the immune system can slightly increase the risk of developing AML.
Radiation
Exposure to radiation and a history of aplastic anaemia may affect the risk of developing childhood AML. Being exposed to ionizing radiation or chemicals such as benzene may also increase the risk.
X-rays
Being exposed to x-rays before birth is thought to increase the risk
Lifestyle factors
Being exposed to cigarette smoke or alcohol before birth may increase the risk of children developing AML
At the moment scientists do not know how to prevent most cases of leukaemia.
Children with a higher risk of leukaemia, children who have been treated with chemotherapy or radiation therapy for an earlier cancer, children who have certain genetic conditions, and children who have received organ transplants should have close follow-ups by their doctor.
At this time, there are no special tests to help find AML early.
Possible signs of childhood AML include fever, feeling tired, and bleeding or bruising easily. Most of the signs and symptoms of leukaemia result from the crowding out of normal blood cells in the bone marrow by leukaemia cells.
Fatigue, loss of appetite or pale skin
A child may complain of shortness of breath or of being very tired. The child's skin may be pale because of the shortage of red blood cells (anaemia). There may also be a loss of appetite.
Extreme tiredness and weakness
One rare but serious symptom of AML is extreme tiredness, weakness, and slurring of speech. This can happen when very high numbers of cells with leukaemia make the blood too thick and reduce the flow of blood to the brain.
Infection
A child with leukaemia may get an infection that doesn't respond to antibiotics, have a high fever, and become very sick. This can happen because there are not enough normal white blood cells. Although children with leukaemia often have very high white blood cell counts, the cells are not normal and do not protect against infection very well.
Easy bleeding or bruising
A child with leukaemia may bruise easily or have increased bleeding from small cuts and nosebleeds. There may be small red spots under the skin caused by bleeding from tiny blood vessels known as petechiae. The bleeding is caused by a lack of blood platelets, which are needed for plugging holes in blood vessels.
Bone pain
Some children will have bone pain, and a smaller number will have joint pain. Leukaemia cells can collect underneath the covering of the surface of the bone or inside the joint.
Swelling and painless lumps
Painless lumps in the neck, underarm, stomach, groin, or other parts of the body. In childhood AML the lumps (called leukaemia cutis) may be blue or purple. There are sometimes lumps around the eyes (called) that may be blue-green.
Swollen lymph nodes
AML can spread to lymph nodes causing them to swell. The child, a parent, or a doctor or nurse might notice swollen nodes on the sides of the neck, in the groin, in the underarm area, or above the collarbone.
Headache, seizures, vomiting
Leukaemia cells can spread outside the bone marrow into the central nervous system, causing headaches and a number of other symptoms.
Rashes, gum problems
Cancer cells can spread to the gums, causing swelling, pain, and bleeding. Spread to the skin can cause spots that look like rashes.
Tests that examine the blood and bone marrow are used to detect and diagnose childhood AML.
The following tests may be used:
Blood cell counts and other blood tests
Most children with leukaemia will have too many white cells in their blood and not enough red blood cells or platelets. The white blood cells tend to be "young" cells normally found in the bone marrow but not in the blood.
A Complete blood count will test
- The number of red blood cells, white blood cells, and platelets.
- The amount of haemoglobin (the protein that carries oxygen) in the red blood cells.
- The portion of the sample made up of red blood cells.
Other blood tests will be done to measure certain chemicals in the blood to tell how well the liver and kidneys are working.
Tumour biopsy
A biopsy of a chloroma tumour may be carried out, the cells will be viewed under a microscope to check for signs of cancer.
Bone marrow biopsy and aspiration
A small piece of bone and bone marrow is removed by inserting a needle into the hipbone or breastbone. A pathologist views the bone and bone marrow samples under a microscope to look for signs of cancer. This test can also be used later to see if the leukaemia is responding to treatment.
Spinal tap (lumbar puncture)
A small needle is placed between the bones in the child's spine in the lower back to draw out some cerebrospinal fluid (CSF). The fluid is looked at for leukaemia cells. A lumbar puncture can also be used to deliver chemotherapy drugs directly into the spinal fluid to prevent the cancer from spreading to the spinal cord and brain.
Lymph node biopsy
An entire lymph node is removed and examined for cancer. If the node is near the skin's surface, this is a simple operation that can be done by numbing just the area around the node. But if the node is inside the chest or abdomen, the child will need general anaesthesia.
X-ray
An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body. An x-ray can be used to see if there is a mass in the chest or leukaemia in the bones or the joints.
Ultrasound
Sound waves are used to produce images of internal organs. This test can distinguish solid from fluid-filled masses. Ultrasound can be used to help show if there is leukaemia in the kidney, spleen, or liver.
CT scan (computed tomography)
A kind of x-ray in which a beam moves around the body, taking pictures from different angles. CT scans are not often used in leukaemia, but they can show if there is disease in the lymph nodes of the chest or in back of the abdomen.
MRI (magnetic resonance imaging)
Powerful magnets and radio waves are used to produce detailed, computer-generated pictures of the body. This scan might be used when there is concern about leukaemia invading the brain.
Gallium Scan and Bone Scan
A radioactive chemical is injected which then collects in areas of cancer or infection. These tests can help to detect infection or cancer in the bones.
The treatment options depend on the type of leukaemia. Chemotherapy is the main treatment for nearly all types of leukaemia including AML. Unlike most other cancers, surgery rarely has any role in the treatment of leukaemia. This is because leukaemia is a disease of blood and bone marrow and cannot be cured with surgery.
Chemotherapy
Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells from dividing. The way the chemotherapy is given depends on the type of cancer being treated. AML treatment will usually involve higher doses of chemotherapy over a shorter period of time than ALL.
Intrathecal chemotherapy may be used to treat childhood AML that has spread, or may spread, to the brain and spinal cord. Intrathecal chemotherapy is given in addition to chemotherapy by mouth or vein.
Side effects of chemotherapy
While chemotherapy drugs kill cancer cells, they can also damage normal cells. This happens because they target cells that are growing quickly such as cancer cells. But in the process they also damage other fast-growing cells. The lining of the mouth and intestines, hair, and blood cells all grow quickly and are likely to be damaged by chemotherapy.
As a result, children being treated with chemotherapy may have a higher risk of infection (from low white blood cell counts), may bruise or bleed easily (from low blood platelets), and tire easily (from low red blood cell counts). Other side effects of chemotherapy can include temporary hair loss, nausea, vomiting, diarrhoea, mouth sores, and loss of appetite.
These side effects usually go away shortly after treatment ends. And there are often ways to manage these side effects during treatment.
Tumour lysis syndrome is a side effect of chemotherapy caused by the rapid breakdown of leukaemia cells. When these cells die, they release substances into the bloodstream that can affect the kidneys, heart, and nervous system. Giving the child extra fluids or certain drugs that help rid the body of these toxins can prevent this problem.
Organs that could be damaged by chemotherapy include the kidneys, liver, testes, ovaries, brain, heart, and lungs. With careful monitoring, such side effects are rare.
One of the most serious side effects of ALL treatment is the chance of the child's developing a second leukaemia, usually AML. This happens in a small number of children after they have been given certain types of chemotherapy drugs. This risk must be balanced against the clear benefit of treating a life-threatening disease such as leukaemia with chemotherapy.
Radiation therapy
Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells. External radiation therapy may be used to treat childhood AML that has spread, or may spread, to the brain and spinal cord. External radiation uses a machine outside the body to send radiation toward the cancer.
Bone marrow or Stem cell transplantation
Stem cell transplantation is a method of giving chemotherapy and replacing blood-forming cells that are abnormal or destroyed by the cancer treatment. Stem cells (immature blood cells) are removed from the blood or bone marrow of the patient or a donor and are frozen and stored. After the chemotherapy is completed, the stored stem cells are thawed and given back to the patient through an infusion. These reinfused stem cells grow into (and restore) the body's blood cells.
Side effects of stem cell transplantation
Stem cell transplantation is a complex treatment and requires a lengthy hospital stay.
Other drug therapy
Arsenic trioxide and all-trans retinoic acid (ATRA) are anticancer drugs that kill leukaemia cells, stop the leukaemia cells from dividing, or help the leukaemia cells mature into white blood cells. These drugs are used in the treatment of a subtype of AML called acute promyelocytic leukaemia.
Biologic therapy
This treatment is currently being tested in clinical trials. Biologic therapy is a cancer treatment that uses the patient's immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body's natural defences against cancer. This type of cancer treatment is also called biotherapy or immunotherapy.
Monoclonal antibody
This is a type of biologic therapy also at the trial stage. Monoclonal antibody therapy is a cancer treatment that uses antibodies made in the laboratory, from a single type of immune system cell. These antibodies can identify substances on cancer cells or normal substances that may help cancer cells grow. The antibodies attach to the substances and kill the cancer cells, block their growth, or keep them from spreading. Monoclonal antibodies are given by infusion. They may be used alone or to deliver drugs, toxins, or radioactive material directly to cancer cells.
World
- World-wide over 250,000 people are diagnosed with Leukaemia each year.
- Leukaemia accounts for 2.5% of all cancers
- Generally rates are higher in Caucasian populations
Europe
- There are approximately 66,000 new cases of Leukaemia in Europe each year.
- 2.4% of cases are attributable to occupational exposure.
- Across Europe there appears to be more variation in rates for males than in females.
- The highest male death rate is in Luxembourg almost twice as high as that in the Netherlands.
- The highest female death rate is also in Luxembourg and is less than 50% higher than the lowest rate in Austria.
UK
- Leukaemias represent 2.5 % of all cancers in the UK
- There are approximately 6,600 new cases diagnosed in the UK each year
- There are 2,000 new cases of AML each year in the UK
- AML accounts for 30% of all childhood leukaemias
Trends
- In Europe there was a 10% decrease in mortality for leukaemia between 1988 and 1997. This is partly because of advances in treatment.
- It is thought the decline represents 7,000 deaths a year that have been avoided.
- Incidence rates in Britain for all leukaemias combined have increased slowly. This could be because of better diagnostic tools and registration of cancers.
- In Britain rates of AML have increased steadily.
Socio economic
In England and Wales incidence rates of leukaemia are marginally higher in more affluent groups.
Survival
There has been dramatic improvement in the survival of children with leukaemia because of advances in treatment and more specialist care.
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